It's called "eh" for a reason. Anywone ever watched South Park, well my friends told me that all the Canadians talk like that, with their heads opening and closing. Canadians say "eh", so yeah.
No it doesn't. It's a disease of pokemon. No, It's not a lie. My pokemon got it randomly, and I didn't cheat or anything. It temporarly boosts your party's experience, and if some of your pokemon are infected, it might spread, which I think is good. I was freaking out when the nurse told me about it, because I didn't know what it was.